Download Understanding 2015 Changes to NFPA 70E

UNDERSTANDING 2015
CHANGES TO NFPA 70E
Safety-related work practices
and maintenance requirements
mandate more robust electrical
safety programs for commercial
and industrial facilities
TWO STAGE POWER DISTRIBUTION
Executive Summary
Every three years, the National Fire Protection Association (NFPA) updates NFPA 70E: Standard for Electrical Safety in the
Workplace®. In recent years, the standard has become increasingly stringent in response to the increased understanding of
electrical accidents in industrial plants and facilities. Because of the severe and often devastating consequences of arc flash
incidents—which claim one life every workday—NFPA, along with the Occupational Safety and Health Administration (OSHA), is
mandating and enforcing safer electrical work practices.
Industrial facilities and plants are often challenged when it comes to making electrical safety policy changes in order to keep up
with the new requirements. However, making every effort to comply is essential to avoiding costly fines, as well as protecting a
facility’s equipment and its greatest asset: its employees.
With the assistance of a well-qualified, professional electrical engineering or electrical testing service provider, facilities can
efficiently and cost-effectively evaluate, update, and maintain their electrical safety programs to ensure compliance and a safe
work environment for employees.
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Understanding the Severity of
Arc Flash Hazards
In the last 10 years, the U.S. Bureau of Labor Statistics
reports 2,000 fatal and more than 24,000 non-fatal electrical
injuries such as those sustained from an arc flash. Arcing
from an electrical fault can produce temperatures hotter
than the surface of the sun, creating an incredibly hot blast
with force similar to an explosion—enough to throw a
worker’s body across the room. The National Safety Council
reports that electrical hazards like this cause nearly one
fatality every single workday.
Obviously, the consequences of arc flash are devastating.
Beyond the risk of personal injury and death, arc flashes can
also lead to business disruption, costly damage to
equipment and facilities, legal liability, increased insurance
premiums, and hefty regulatory fines.
The problem isn’t going away. Rather, due in part to
greater overall energy usage, as well as higher system
voltages and available fault currents, the danger of exposure
to arc flash hazards is on the rise and increasing steadily. To
help reduce the risk and protect workers, NFPA develops
and regularly updates its guidelines for creating a safe
electrical work environment.
The Role of NFPA 70E
As the world’s leading advocate of fire protection, NFPA has
published more than 300 consensus codes and standards,
including NFPA 70E: Standard for Electrical Safety in the
Workplace. Designed at the request of OSHA, the intent of
the standard is to reduce exposure to the hazards of shock,
electrocution, arc flash, and arc blast while working on or
near exposed electrical conductors or circuit parts that are
or can become energized.
NFPA 70E undergoes updates and revisions every three
years. Each edition introduces significant changes designed
to help prevent the devastating effects of electrocution and
arc flash incidents. Even more changes have appeared in the
2015 edition, including additional essential updates in the
areas of safety, maintenance and training. NFPA 70E 2015
became effective in August 2014. While not yet an OSHAenforceable document in its entirety, NFPA standards are
used as part of electrical safety practices and are often
referenced as part of an OSHA citation.
This paper provides an overview of the safety
and maintenance changes in NFPA 70E 2015 that most
impact the electrical safety programs in place at industrial
facilities and among other major power users.
A Look Back at NFPA 70E 2012
Many facility managers have likely made changes to work
practices and electrical safety programs based on the
updates in NFPA 70E 2012, which became effective August
31, 2011. The most relevant changes impacted safety-related
work practices, work involving arc flash hazards, and
electrical distribution system maintenance.
Specifically, NFPA 70E stipulated the following:
Safety-Related Work Practices (Article 110)
yyEmployers must now document meetings with contract
employees in which information about known hazards is
communicated, thus enabling contractors to make proper
hazard assessments. This stipulation also appears in
OSHA’s 29 CFR 1910.269 revisions, which require
divulging incident energy levels for contractors.
yyEmployees who work around—not just on—energized
electrical equipment must be safety trained, preferably
via an instructor-led course as opposed to web-based
training. Retraining must occur at least every three years,
and all training must be documented.
yyFacilities must conduct annual inspections to ensure
each employee is complying with safety-related work
practices. The annual audit requirement is extended to
field work as well.
yyAt least once every three years, facilities must audit their
own safety policy and training programs to ensure
compliance with the standards. The audits need to be
documented, and if deficiencies are identified, revisions
must be made to bring all elements of the safety
program into compliance.
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TWO STAGE POWER DISTRIBUTION
Work Involving Arc Flash (Article 130)
Terminology Changes—Risk vs. Hazard
yyFacility managers must ensure that arc flash hazard
labels include information such as nominal system
voltage, arc flash boundary, and guidance on the
required level of personal protective equipment (PPE).
In the 2015 version of NFPA 70E, the standard committee
has attempted to separate and better define “risk” and
“hazard.” For the purposes of the standard, hazard
identification primarily refers to the potential for harm from
exposed energized electrical conductors and/or the
condition of the equipment. Risk primarily refers to the
chance or probability that the identified hazard could result
in physical harm to the worker, or the unqualified or
unprotected persons nearby.
yyFacility managers must document the calculation
method and the data that supports the information on
the arc flash labels.
yyArc flash labeling is required for DC equipment in
addition to AC equipment.
General Maintenance Requirements
(Articles 200 through 250)
yyFacility managers must now conduct maintenance on
electrical equipment in accordance with manufacturers’
instructions or industry consensus standards. Previously,
maintenance was only specified for overcurrent
protective devices.
yyFacility managers must maintain a current single-line
diagram in legible condition.
yyDocumentation is now required for overcurrent
protective devices to show they have been properly
maintained, tested and inspected.
New Changes for 2015
Building on the safety, training, and maintenance
requirements outlined in the 2012 edition of NFPA 70E, the
2015 version of the standard introduces additional changes
that facilitate an even greater understanding, awareness,
and mitigation of electrical hazards. While some of the 2015
updates are editorial or informational in nature, others
require facility managers to once again take action to revise
and update safety policies to better protect workers and
ensure regulatory compliance.
Specifically, facility managers need to be aware of the
following updates to NFPA 70E 2015:
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The terms “risk” and “risk assessment” have also been
clearly defined:
yyRisk - “A combination of the likelihood of occurrence of
injury or damage to health and the severity of injury or
damage to health that results from a hazard.”
yyRisk Assessment - “An overall process that identifies
hazards, estimates the potential severity of injury or
damage to health, estimates the likelihood of occurrence
of injury or damage to health, and determines if
protective measures are required.”
Risk assessment is now the key to determining the necessity
to use PPE.
As a result of these changes, the terms “arc flash hazard
analysis,” “shock hazard analysis,” and “electrical hazard
analysis” have all been removed from the language in the
standard. These items are now referred to, respectively, as
“arc flash risk assessment,” “shock risk assessment,” and
“electrical risk assessment.” Additionally, Hazard Risk
Categories (HRC) have been eliminated and are now
referred to as “Arc Flash PPE Categories.” Finally, shock
protection requirements are now assessed separately from
arc flash protection requirements.
In line with the effort to better define risks to workers, the
standard committee has also made attempts to more clearly
indicate situations where additional or substantial risk is
unlikely to exist. For example, the standard makes it clear
that workers do not need to take special measures to
protect themselves when performing routine operations on
electrical equipment that is properly installed and
maintained. Specifically, the standard states that normal
operation, such as switching, is allowed without any special
PPE if all the following exist:
yyThe equipment is properly installed
yyThe equipment is properly maintained in accordance
with manufacturer’s specifications or industry
consensus standards
yyDoors are closed and secured
yyCovers are in place and secured
yyThere is no evidence of impending failure
Defining Qualified Workers
Both OSHA and NFPA recognize the importance of
determining a worker’s qualifications to work on or around
electrical equipment. To help employers make this important
designation, NFPA 70E 2012 states that a qualified person
shall be trained and knowledgeable in the construction and
operation of equipment or specific work methods, and be
trained to recognize and avoid the electrical hazards that
might be present with respect to that equipment or work
method. It is important to note that a person can be
considered qualified with respect to certain equipment and
methods, but still be unqualified in other situations.
NFPA 70E 2015 also adds that qualified electrical workers
permitted to work within the limited approach boundary of
exposed energized electrical conductors and circuit parts
operating at 50 volts or more must have additional training
in minimum approach distances to exposed parts.
Employees who respond to medical emergencies must also
participate in refresher training per the new standard.
SHOCK HAZARD BOUNDARY
DEFINITIONS IN NFPA 70E
Limited Approach Boundary: A risk of shock exists
within this boundary. Unqualified persons may enter this
area if they are under the supervision of a qualified worker
and using proper PPE.
Restricted Approach Boundary: Qualified personnel
only. Requirements are the same as if working on or near
energized circuits. Insulated gloves, tools, and equipment
are required within this boundary.
Prohibited Approach Boundary: Removed from
NFPA 70E 2015.
NFPA 70E 2015 Article 130.4(B) states: “The shock
protection boundaries identified as limited approach
boundary and restricted approach boundary shall be
applicable where approaching personnel are exposed to
energized electrical conductors of circuit parts.”
The 2015 version of the standard adds the requirement that
such a person shall demonstrate the ability to use—and not
just be familiar with the proper use of—the following:
yySpecial precautionary techniques
yyPPE including arc flash suits
yyInsulating and shielding materials
yyInsulated tools and test equipment
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TWO STAGE POWER DISTRIBUTION
Arc Flash Risk Assessments
A major revision in the 2012 NFPA 70E update stated that
the arc flash boundary distance must now be determined for
all locations where the voltage is greater than 50 volts and
there is a possibility of performing energized work such as
maintenance, diagnostics and testing. Previously, a number
of locations could be excluded from the assessment and
calculation based on system voltage and the limits of
the supplying energy source. For example, a 208-volt
distribution panel for lighting and convenience outlets may
not have been assessed or labeled because the supplying
transformer was less than 150 kilovolt-amperes. However, a
second adjacent panel did need to be assessed and labeled
because it was fed from a larger transformer. Such anomalies
led to much confusion in the field. So while the new standard
expands the scope of arc flash protection and the number of
locations that need to be assessed, it also helps eliminate
uncertainty that could lead to noncompliance, or worse,
injury to a worker.
In years past, the standard was also vague and not well
defined regarding whether the arc flash boundary distance
would have to be manually calculated or if it could be
assumed using tables supplied in the standard. While the
“table method” of determining the boundaries costs nothing
to use and is easier to implement than an analysis, the tables
are often misused in the field, which can put workers at risk.
As a result, provisions in the new 70E make it clear that
the intent of the standard committee is to encourage the
use of engineering analyses over the “table method.”
Specifically, Article 130.5(C)(1) recommends performing an
engineering analysis using one of the recognized means
such as Institute of Electrical and Electronic Engineers’
Guide for Performing Arc Flash Calculations (IEEE 1584).
However, Article 130.5(C)(2) does allow the use of the tables
at 130.7(C)(15), so long as the system parameters and task
meet the table requirements.
In other words, the tables may only be used if:
yyThe specific task to be performed appears in the tables
yyThe system meets the listed criteria for short
circuit current magnitude and speed of response of
circuit protection
If the task does not appear in the table, or if the system
does not meet the criteria found in the tables, then the
tables cannot be used. Keep in mind that in many cases,
facility managers do not have access to the data and
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information needed to use the tables correctly. In this case,
an engineering analysis must be performed.
Although not new in 2012 or modified in 2015, it is important
to emphasize that the arc flash risk assessment shall be
updated when a major modification or renovation takes
place and that it shall be reviewed periodically, not to exceed
five years, to account for changes in the electrical
distribution system (or regulatory guidance).
Arc Flash PPE
While proper PPE can be life-saving, far too often,
employees have not selected or used the proper PPE in
order to complete their jobs safely. IEEE reports that 2,000
workers are admitted to burn centers for extended injury
treatment caused by arc flash every year.
As described above, there are clearly two separate
methods for assessing arc flash risks and determining arc
flash protection and PPE requirements. The first method is
to perform an engineering analysis. The second “table
method” can be used only where the system parameters
defined in the tables are applicable to the specific tasks
being performed.
Method 1—Engineering Analysis
Method 2—Table Method
The results of an engineering analysis are placed on the
equipment label in the form of incident energy (in calories per
square centimeter at working distance). The worker would then
need to select PPE with an Arc Thermal Performance Value
(ATPV) that meets or exceeds the available incident energy
posted on the informational label. ATPV is also rated in calories
per square centimeter to make this determination simple.
In the past, the NFPA 70E “table method” for choosing
arc-rated (previously called flame resistant) clothing was
somewhat cumbersome. This method could also be
ineffective, as tasks in the old tables were often lumped
together, regardless of system characteristics, ultimately
leading to improper PPE requirements.
Notice there is no mention of PPE categories. In fact, the
results of an incident energy analysis to specify an arc flash
PPE category in Table 130.7(C)(16) is not permitted. Table
130.7(C)(16) was specifically created to complement the task
tables and is applicable only if using the “table method.”
Therefore, facilities that conduct an engineering analysis
must use the results to create site-specific arc flash
protection and PPE requirements. Reducing and managing
incident energy exposure through engineering analysis can
significantly impact and potentially reduce the required PPE
for performing tasks on electrical equipment, a benefit that
cannot be gained using the task tables and charts.
For example, if an engineering analysis determined an
incident energy value of 8.4 calories, and that value was
recorded on the label, then the worker would need to
choose a garment with an ATPV that meets or exceeds the
posted 8.4 calories. However, using the previous “table
method,” an 8.4 calorie hazard would be considered
Category 3. Most employers do not provide Category 3 PPE,
but they do offer Category 4 PPE. In such a case, the worker
would be required to wear Category 4 protection for a
calculated Category 3 hazard. Using the incorrect PPE or
more PPE than required becomes cumbersome and could
actually be more detrimental to worker safety. Using the
engineering analysis to determine PPE requirements ensures
the most appropriate PPE for the hazard, and thus, the
greatest protection for the worker.
The 2015 version of the standard introduces a new multitable format for choosing arc-rated clothing and PPE. Major
revisions have been made to the table for determining risk,
and additional tables have been added to determine proper
PPE if a risk exists.
Workers first look to Table 130.7(C)(15)(A)(a) to determine if
arc flash PPE is required. This task-based table covers both
AC and DC applications and indicates if there is an arc flash
hazard associated with each specific task—yes or no. If
there is an arc flash hazard, workers move to Table 130.7(C)
(15)(A)(b) or 130.7(C)(15)(B) to find the arc flash PPE
category. They then refer to Table 130.7(C)(16) which lists
the clothing and other PPE required for that category.
Workers must wear all of the PPE listed.
The tables contained within NFPA 70E provide some basic
guidelines for common tasks, but even the tables require
system information that may not be known. As described
above, if the task is not in the tables, or the system
parameters defined in the tables are not met, then an
engineering analysis must be performed to determine what
level of arc flash protection will be required.
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Arc Flash Labeling
Arc flash labeling became an NFPA 70E requirement in
2002, and the requirements were updated in 2004, 2009,
2012 and 2015. As recently as 2009, the standard stated
only that electrical equipment had to be labeled, and listed a
few of the types subject to marking, but was somewhat
unclear in detail. In 2012 and 2015, NFPA clarified the intent
of the requirement.
Specifically, NFPA 70E 2015 spells out the types of
equipment that need to be labeled, including switchboards,
switchgear, panel boards, industrial control panels, meter
socket enclosures, and motor control panels. The new
standard also makes it clear what information needs to be
included on field labels:
yyNominal system voltage
yyArc flash boundary
yyAt least one of the following:
• Available incident energy and the corresponding
working distance, or the arc flash PPE category in
Table 130.7(C)(15)(A)(b) or Table 130.7(C)(15)(B) for
the equipment, but not both
• Minimum arc rating of clothing
• Site-specific level of PPE
Today’s standards specify a number of exceptions to arc
flash labeling requirements. They state that only electrical
equipment that is likely to require examination, adjustment,
servicing, or maintenance while energized needs to be field
marked. For example, a fractional horsepower motor
disconnect in a 3-phase motor control center would likely
require PPE, yet a local wall-mounted disconnect for the
same motor (that requires a label) may not call for arc flash
PPE due to the location’s inherently low level of incident
energy. Only a risk assessment can determine the need and
should be performed on a case-by-case basis.
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Additionally, NFPA 70E section 130.5 includes an exception
that permits labels applied prior to September 30, 2011, as
long as those labels contain the available incident energy or
required level of PPE. It is important to note that some
existing labels may contain both incident energy at working
distance and arc flash PPE category. This is acceptable only
until the labels come due for review (the review period for
arc flash labels is at least once every five years). At such
time, new labels must be applied indicating one, but not
both, pieces of information.
Clarification is also provided around the need to keep labels
up to date. Language in 130.5 says that labels need to be
updated if the arc flash hazard risk assessment shows that
the labels are inaccurate. The standard clearly indicates that
the owner of the electrical equipment is responsible for
documentation, installation, and maintenance of the
field-marked label.
Obviously, major changes to the electrical distribution
system have the potential to impact the accuracy of arc
flash labels, and thus, the risk to electrical workers. However,
replacing a fuse, replacing a circuit breaker or protective
relay, and even changes made by supplying utilities
can affect arc flash analysis and the resulting field label
information. To ensure compliance and worker safety, a
qualified engineering company should ideally assist with an
arc flash assessment and label review when any changes
are made to the distribution system, or every five years at
a minimum.
Energized Electrical Work
Permit Requirements
Some facility managers contend that adopting NFPA 70E is
a cumbersome and time-consuming process, especially the
development of risk assessments and energized electrical
work permits. It is important to note that newer versions of
NFPA 70E limit areas where electrical work permits are
required to those areas within the limited approach
boundary or arc flash boundary.
Specifically, energized electrical work permits are
required when:
yyWork (repair or replacement of components) is planned
within the limited approach boundary of exposed
energized conductors or circuit parts
yyAn increased risk of an arc flash exists (even) with doors
closed and covers on
Additionally, the recommendation to perform a risk
assessment and develop a written energized electrical work
permit plan for hazard mitigation applies to those tasks that
are not routine in nature, or performed less frequently than
once a year. If the task is performed frequently, an original
risk assessment with successful mitigation techniques
should already be in place. Thus, another assessment is
not required.
Specifically, NFPA 70E 2015, Article 130.2(B)(3) Exemptions
to Work Permit says that an energized work permit is not
required for work performed on or near live parts when
qualified persons are performing tasks such as testing,
troubleshooting, or voltage measuring; thermography and
visual inspection up to the restricted approach boundary
(RAB); access/egress with no electrical work within the RAB;
and general housekeeping up to the RAB, as long as
appropriate safe work practices and PPE is provided
and used.
Figure 1: Field testing labels help satisfy documentation requirements
of NFPA 70E 2015.
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General Maintenance Requirements
Battery Risk Assessment Requirements
Building on the general maintenance requirements
established in NFPA 70E 2012, the newest version of the
standard reiterates that qualified persons who perform
maintenance on electrical equipment and installations shall
be trained and familiar with the specific maintenance and
test procedures required. Additionally, the 2015 version
requires maintenance for protective devices in order to
adequately withstand or interrupt available fault current.
NFPA 70E specifies that electrical safety programs should
include risk assessment procedures to address employee
exposure to electrical hazards. New in 2015, this stipulation
also applies to battery work. Specifically, Article 320.3(A)(1)
states: “Prior to any work on a battery system, a risk
assessment shall be performed to identify the chemical,
electrical shock, and arc flash hazards and assess the risks
associated with the type of tasks to be performed.”
Specifically, Article 205.4 requires the inspection and
testing of these devices in accordance with manufacturers’
specifications or industry consensus standards, including
American National Standards Institute/InterNational
Electrical Testing Association Standard for Maintenance
Testing Specifications (ANSI/NETA MTS), IEEE 3007.2,
and NFPA 70B. Furthermore, the results of these
maintenance activities must be documented and maintained.
An informational note states: “Improper or inadequate
maintenance can result in increased opening time of the
overcurrent protective device, thus increasing the incident
energy.”
Specific battery-related tasks are now included in the
newly revised DC task-based tables, indicating if an arc flash
hazard is associated with such tasks. The tables currently
offer the best method for assessing and evaluating
battery-related risks and selecting the appropriate PPE.
NFPA 70E 2015 now specifies that the equipment owner is
responsible for electrical equipment maintenance and the
documentation of such maintenance. The latest edition of
the standard added IEEE 3007.2 Recommended Practice for
the Maintenance of Industrial and Commercial Power
Systems as a guideline for maintenance frequency, methods,
and tests, along with NFPA70B and ANSI/NETA MTS.
Common industry practice is to provide date and overall
condition of the specific devices that have been tested and
maintained in the field via a test or calibration decal. This
provides immediate indication of the last maintenance date
and if it was found acceptable. This can assist the employee
in the assessment of the overall electrical equipment
maintenance status.
In conjunction with the assessment, it is important to review
the warning signs or labels regarding shock hazard due to
the battery voltage and the arc flash hazard due to the
prospective short circuit current and thermal hazard.
Well-qualified, professional electrical engineering service
providers who specialize in battery services can be
instrumental in identifying battery-related risks; performing
battery work in compliance with all industry standards; and
mitigating risks to electrical workers.
Has an arc flash hazard
analysis been conducted?
YES
NO
Does the task involve the
possibility of an arc?
YES
Thermal hand
protection is
required.
Go to arc flash
risk assessment.
NO
Thermal PPE is not required when the
risk of a thermal incident
happening is acceptable.
Go to arc flash
risk assessment.
Figure 2: The thermal risk assessment process for a battery system
illustrates how the likely exposure depends on the type of task
being performed.
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Additional Changes and Complete Details
For more information on the changes outlined in this white
paper, please refer to the 2015 NFPA 70E Handbook
available at NFPA.org. You can also refer to the most current
edition of ANSI/NETA MTS.
A Note About OSHA
NFPA is not the only organization requiring facilities to
upgrade their electrical safety practices. Due to increasing
awareness of the frequency and the severity of the electrical
arc flash hazard, OSHA updated standard CFR 1910.269 in
the Federal Register on April 11, 2014, representing the first
time OSHA is mandating and enforcing specific arc flashrelated requirements (beyond general hazard awareness) for
higher voltage facilities.
Effective October 31, 2014, the new revisions to OSHA CFR
1910.269 address the frequency and magnitude of arc flash
hazards in high-voltage utilities and industrial facilities that
operate power generation, transmission, and distribution
equipment. The OSHA revisions are patterned after the
latest consensus standards, including NFPA 70E, ANSI/IEEE
C2 National Electrical Safety Code, and other improvements
in electrical safety technology. They require utilities and
industrial facilities to make significant changes to training,
host employer requirements, fall protection, the
requirements to estimate arc flash energy, minimum
approach distances, PPE, and a number of other
work practices.
For more details on the OSHA revisions, see the following
white paper, published by Vertiv™: OSHA Publishes FirstEver Arc Flash Protection Requirements for the Electric
Power Generation, Transmission, and Distribution Industry.
Implementing the New Electrical
Safety Requirements
It can be challenging for major power users and industrial
facilities to comply with the increasingly stringent electrical
safety requirements outlined in NFPA 70E. However,
establishing an effective safety program per the guidelines
can promote system performance and efficiency and
prevent costly OSHA fines. Even more important, it can
reduce injuries and lost worker productivity. It could
even save the life of an employee working at your business
or facility.
Industry experts, including the NETA-certified engineers and
field technicians at Vertiv’s Electrical Reliability Services,
strongly recommend partnering with professional electrical
engineering or electrical testing service providers that are
well trained and well versed in the new requirements. While
there is no legal requirement for a Registered Professional
Engineer to perform arc flash hazard analysis, such expertise
not only ensures compliance with the standards, it can also
save lives since improper calculations can put workers in
grave danger.
As a first step toward compliance with safety requirements,
Vertiv recommends performing a comprehensive
professional site review and compliance assessment. It will
evaluate current safety practices in your plant or facility and
identify any areas of risk or non-compliance. Based on the
results, your chosen service partner should offer capabilities
to customize and implement a complete, cost-effective
solution designed to bring your facility up to standards in
the most efficient way possible, along with an ongoing plan
to maintain compliance.
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Best Practices Help Ensure Compliance
Preventive Maintenance
Vertiv recommends the following elements and best
practices as part of a comprehensive, effective electrical
safety program that complies with OSHA, NFPA, and other
relevant industry guidelines.
An optimized preventive maintenance strategy evaluates the
condition of your equipment and determines the most costeffective and manageable solution to ensure the equipment’s
overall performance, safety and reliability. By maintaining all
electrical equipment, you can help ensure worker safety and
prevent unplanned downtime. NFPA 70E specifically requires
maintenance for electrical equipment and overcurrent
protection devices to help mitigate arc flash hazards.
10 BEST PRACTICES FOR
COMPLYING WITH NFPA 70E
1
Preventive Maintenance
2
Arc Flash Risk Assessment
Such equipment would include:
yySubstations, switchgear assemblies, panelboards, motor
control centers, disconnect switches
yyInsulated conductors, grounds and busduct
yyTransfer switches and control equipment
3
Labeling and Hazard Communication Plan
4
Design and Methods Review
5
Accurate Single-Line Diagrams
6
Short Circuit and Coordination Studies
7
Electrical Safety Program Review/Development
8
Arc Flash Training Program and PPE Plan Development
9
Documentation
10
Periodic Reviews
yyCircuit breakers
yyProtective relays
yyMotors and generators
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yyEquipment in hazardous locations
yyBatteries and battery rooms
yyPortable electric tools and equipment
yyPersonal safety and protective equipment including
electrical gloves, hot sticks, and flash suits
Arc Flash Risk Assessment
Accurate Single-Line Diagrams
NFPA 70E requires facility owners to perform an arc flash
risk assessment prior to allowing a worker to perform tasks
on energized equipment. The arc flash risk assessment
determines the presence and location of any arc flash
hazards, calculates incident energy, and determines
appropriate safety-related work practices, arc flash
boundary, and the correct PPE to be worn within the arc
flash boundary.
NFPA 70E requirements mandate accurate, up-to-date and
legible single-line diagrams. These schematics are essential
for documenting, troubleshooting, and communicating
information about your power systems. A comprehensive
site survey is essential to develop or update existing singleline diagrams or to complete electrical system drawings.
To calculate incident energy, technical data is reviewed and
additional data is collected such as equipment type, voltage,
ratings, impedance, and other information. To provide
accurate results, state-of-the-art software should be utilized
to perform the arc flash calculations. The software enables
users to evaluate alternatives quickly and easily in order to
establish an optimal design.
To achieve accurate arc flash hazard results, it is essential
that arc flash calculations be completed using accurate
short circuit calculations and protective device coordination
data. Short circuit and coordination studies calculate
momentary, interrupting, and arcing current values;
compare available fault currents to protective device
ratings; and establish trip settings for all types of protective
devices, which reduce unplanned downtime or outages. It’s
important to select an expert that specializes in
conducting these studies to ensure compliance with NFPA
and OSHA requirements.
Labeling and Hazard Communication Plan
Electrical equipment such as switchboards, panelboards,
industrial control panels, and motor control centers that are
likely to require maintenance while energized, must be field
marked with a label, and the labels must be reviewed no less
than once every five years. Specific requirements for what
must be included on the labels are outlined in NFPA 70E
Article 130.5.
The new requirement in NFPA 70E 2015 to analyze and label
all equipment operating at greater than 50 volts may be
somewhat costly due to the number of additional
calculations required.
Design and Method Reviews
A protection scheme design review and operational
assessment of your electrical distribution system should be
conducted to identify and reduce potential electrical
hazards. Several areas to evaluate include fault current
levels, arc exposure times, operational procedures (such as
remote breaker control and remote racking), and system
grounding. Experts can assist with mitigation strategies to
alter the current protection scheme, which can significantly
reduce fault levels, arcing time, arc incident energy, and arc
blast force.
Short Circuit and Coordination Studies
Electrical Safety Program Review/Development
An effective electrical safety program should be designed to
support and complement the facility’s overall site safety
program. It should provide training and awareness of the
potential electrical hazards, and specifically arc flash, to
all employees.
At a minimum, the program should identify hazard/risk
evaluation procedures, electrically safe work procedures,
tools and PPE, and risk mitigation strategies. The electrical
safety program must be documented and audited at least
every three years to verify the principles and procedures are
in compliance with NFPA 70E.
Arc Flash Training Program and
PPE Plan Development
Developing a specific arc flash training program and
complementary PPE plan based on the findings of the arc
flash analysis can ensure workers fully understand electrical
and arc flash hazards and how to mitigate the risks. The PPE
plan should provide specific protection requirements and
recommendations based on findings of the arc flash analysis.
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Documentation
Keeping comprehensive and proper documentation can
ensure compliance with NFPA 70E and OSHA standards
and can help facilitate an investigation should an arc
flash-related injury occur.
Documentation should include the results of the arc
flash analysis and any other studies, as well as a written
recording of incident energy at working distances, flash
protection boundary, hazard/risk category, and other
pertinent information such as voltage, available fault
current, protective device description and its trip time, arc
gap, and arc current. Documentation of worker training is
also required.
Periodic Reviews
The 2015 edition of NFPA 70E clarified the intent of and
suggested frequency for periodic reviews/updates of arc
flash assessment information and worker training programs.
Such reviews can help maintain ongoing compliance with
arc flash standards, practices and regulations, and ensure
that any changes, modifications or expansions to an
electrical distribution system meet the latest arc flash
requirements.
Per the standard, the arc flash assessment must be
reviewed whenever significant changes are made to the
system, or at most, every five years. The corporate safety
policy must be reviewed every three years to stay in
compliance with the latest updates to NFPA 70E. Individual
worker reviews, or audits, must be performed annually, and
the results must be documented. If these audits find that
the principles and procedures of the electrical safety
program are not being followed, appropriate revisions to the
training program or revisions to procedures must be made.
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Conclusion
Electrical power has always come with risks, and potential hazards, including arc flash, are on the rise. Organizations such as
OSHA and NFPA have become increasingly proactive about providing and enforcing guidelines and standards for mitigating the
risk and ensuring worker safety. The most recent version of NFPA 70E requires facility owners and managers to revise and update
safety policies, including performing power system studies to calculate and document arc flash risks.
Compliance with the revised standards can be a challenge for many major power users and industrial facilities. However,
partnering with a qualified electrical service provider to evaluate, update, and maintain safe work practices can help industrial
facilities and power users make great strides in implementing best practices for protecting their people, their businesses, and their
bottom lines.
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WP-02-004 (R3/17)